<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>堆叠属性【固定定位，相对与绝对定位】</title>
		<style>
			.taiyi{
				width: 300px;
				height: 300px;
				background-image: url(img/1.png);
				background-size: 100% 100%;
				/*绝对定位，脱离文档流*/
				position: absolute;
				/*z-index属性：使用之前元素上必须有【固定，想对】或者相对绝对z-index*/】
			   z-index: 1000;
			}
			.shengongbao{
				width: 300px;
					height: 300px;
					background-image: url(img/4.png);
					background-size: 100% 100%;
					position: absolute;
				
			}
		</style>
	</head>
	<body>
		<div class="taiyi"></div>
		<div class="shengongbao"></div>
	</body>
</html>